Internal rotary valve actuator system

ABSTRACT

An actuator system for controllably rotating a rotary (valve) element positioned in a pressurized fluid vessel. A double-acting piston-cylinder intermittently rotates a ratchet wheel operatively connected to the rotary element. The cylinder is sealed within a bellows chamber assembly in the vessel and is controllable by a pressure source positioned outside of the vessel. The wheel is rotated by a ratchet member biased against the ratchet wheel and attached to the cylinder and reciprocable therewith. A ratchet pawl biased against the ratchet wheel prevents the reverse rotation of the wheel, and thereby of the rotary element.

This is a continuation of Ser. No. 594,151 filed Oct. 9, 1990, nowabandoned.

BACKGROUND OF THE INVENTION

The present invention relates to devices for controllably actuatingrotary elements positioned in adverse or hostile environments. It moreparticularly relates to externally operable systems for actuating rotaryvalves positioned within pressurized fluid containment or transportvessels.

Society today requires that numerous chemical materials be handled, manyof which have hazardous or obnoxious properties. These materials includefor example acids, alkalies, chlorine, ammonia, liquified petroleumgases, hydrogen sulfide, hydrogen cyanide, sulfur dioxide, mercaptans,fuels, pesticides, radioactive materials, and industrial wastes. Toinsure that these hazardous, obnoxious, or valuable or sensitivematerials do not escape into the environment during their processing,storage and transportation they must be contained in strong vessels orpiping systems. These vessels and piping systems must not only providesatisfactory access to the contained materials, but must completely andsafely contain them at all times when the escape thereof to the outsideenvironment is undesirable or unsafe. In some cases, it is evendesirable to protect the material itself from the environment.

The unintentional escape of such substances from their containers canhave disastrous consequences, including the loss of life, damage tohealth or property, public inconvenience and even the mass evacuation ofpublic areas. Accordingly, there is a strong need to provide safercontainment systems. Although totally sealed vessels providing no accessto the outside can be designed to be highly reliable, access to thematerials stored in them is of course necessary. Valves with or withoutmechanical actuator devices to operate them are therefore provided. Thecontainment vessels are typically reliably built and it is the valvesthereof which are the weak points in the system and thereby reduce thereliability and usefulness of the entire containment system.

In some instances, relatively large leaks or seepage rates from valvesare tolerated by users and by society depending upon the particularlocation and the state, pressure and properties of the stored materialswhether hazardous or nonhazardous. However, in the case of extremelytoxic, reactive, obnoxious, valuable or sensitive materials even smallfailures of containment or seepages can be so objectionable as todiscourage or even preclude the handling, transportation or storage ofthem. This problem is growing due to the public's increasing anxietyover the handling of chemical and radioactive materials by both industryand government. Materials which exist in normal conditions as highpressure or liquified gases are particularly troublesome especially ifthe materials have a foul odor or corrosive properties. Seepages may noteven approach hazardous levels before the users of the materials areexposed to adverse publicity, litigation and extremely stringent andcostly regulations. When valve systems used with hazardous, obnoxious orvaluable materials fail, the release of the materials can thus havepotentially lethal and costly consequences. This failure can result fromhighway accidents, fires, explosions, earthquakes, storms, misuse,abuse, and vandalism.

Known valve systems typically comprise a moveable plug assembly or portwhich can be manipulated relative to a valve seat to open or close thevalve. This manipulation is usually done by transferring a mechanicalforce from outside of the valve to the plug or seat by means of a valvestem passing through a packing gland or a mechanical seal. These sealsor glands are dependent upon tight mechanical closures, and theyinvariably leak to some measurable extent. These valves also are subjectto relatively rapid friction wear causing the seals thereof toultimately fail.

Most known valves are also designed such that if they are to be operatedin response to instrumentation or personnel, they must be installedoutside of their containment vessel, usually on a nozzle or an attachedpipe. While the valve body itself might be capable of withstandingexternal exposure to the contained material, the operating extant cannotwithstand such materials or hard pressure. They characteristically aredesigned to operate in gentle conditions of temperature, pressure andatmosphere. Accordingly, valves and valve actuators are now usuallyplaced outside of the containment vessel, accessible to personnel. Thispositioning means however that the valve is relatively vulnerable tomechanical damage and damage by impacts, fires, abuse and so forth whichwould not necessarily damage the containment vessel itself.

To make the valves less vulnerable and more resistant to some types ofexternal hazards, such as fire, protective shielding is sometimes used.Its use is generally limited, however, and as to transportation vessels,it typically increases the vehicle's weight unacceptably.

Specialized internal excess flow valves have been designed to at leastpartially remedy this vulnerability problem. These valves closeautomatically using the system or product pressure at preset flow rates.They do not communicate with the outside environment and cannot becontrolled externally. By necessity they are designed not to closeunless the rate of flow exceeds the maximum expected flow requirementsof the system. They are not adjustable as to response without entry intothe vessel. Unfortunately, the nonadjustability of these valves and theneed to set a flow level higher than the maximum expected flow limitstheir usefulness. Further, unintentional escapes of material throughleaky or partially broken external systems can result in dangerous orobnoxious releases to the environment at flow rates considerably lessthan the maximum expected flow rates. As a result, these valves protectonly against unlikely circumstances involving total downstream failure.

The vulnerability problem has been addressed in a few cases byinstalling the seat and plug portions of the valve within the tank orvessel envelope and placing the mechanical linkage on the outside of thetank envelope. These valves have shaft or stem seals outside of the tankenvelope and they are vulnerable to physical impact as well as to stemseal seepage. The theory is that the external portions of the valve canbe broken or shorn off in an accident and that the internal plug andseat will remain intact. This is unlikely however due the actualmechanical stem linkage of the external system to the internal system.Furthermore, in actual practice, this mounting arrangement is oftendamaged when impacted, leaving the system totally unprotected and apt toleak.

The seal or gland leakage problem has been partially addressed in someknown devices by using bellows or diaphragm seals on the stems ofotherwise conventional valves, or by using magnetically transparentrigid seals through which magnetic forces are transmitted tomechanically manipulate the valve plug or seal, which valves aregenerally referred to as electromagnetic solenoid valves. In the case ofthe bellows or diaphragm seal, the seals are intrinsically weak toaccommodate the low forces provided by conventional valve geometries.They are therefore subject to damage by relatively small forces andcannot withstand the environmental rigors inside containment vessels.

Electromagnetic solenoid valves are limited to small sizes and lowpressure operating ranges due to the practical limitations on the poweror force output of reasonably small magnetic actuators. These devicesattempt to solve the problem of limited force by means of pilot valves.The ports of these devices though are very susceptible to plugging withforeign matter and require that the fluid being contained have a minimumpressure differential relative to the downstream pressure in order forthe valve to move or even to reliably stay in one position.Electromagnetically generated forces, furthermore, utilize electriccurrents sufficient to generate sparks, and therefore are often notsuitable for use around flammable or explosive mixtures. No knowndevices of this type have the ability to operate within the containmentvessel itself.

Valves which are to be operated or controlled from the outside of thevessel are typically designed to be installed outside of the vessel inwhole or in significant part as previously stated. This leaves the valvehighly vulnerable to accidental damage, and susceptible to seal leakageparticularly for high pressure systems. A practical solution to theproblem of externally controlling the action of a valve when the valveis fully contained within a pressure vessel in a manner which preventseven seepage leaks from the control device itself was not known.

SUMMARY OF THE INVENTION

Accordingly, it is a principal object of the present invention toprovide an improved actuator system for rotary elements.

It is another object of the present invention for provide an improvedsystem for actuating rotary valves positioned in high fluid pressurevessels wherein the system is operable from outside of the vessel.

Directed to achieving these objects, a novel actuating system forcontrollably rotating rotatable elements in pressurized fluid vessels(or other adverse or hostile environments) is herein provided. Thesystem includes a ratchet wheel operatively connected to the rotatableelement for rotating it and a ratchet member engageable with and biasedtowards the ratchet wheel. A piston cylinder reciprocator reciprocatesthe ratchet member relative to the ratchet wheel to controllable rotatethe rotatable element. The reciprocator is protectively positionedinside of a sealed chamber assembly for protection from the pressurizedfluid in the containment vessel. The reciprocator is actuable andoperatively connected to a pumping system positioned outside of thevessel. The ratchet wheel, member and reciprocator are all attached to amounting plate secured to an inside wall of the containment vessel. SeeU.S. Pat. Nos. 3,345,915, 3,430,644 and 3,480,034, each of whose entirecontents are hereby incorporated by reference.

Other objects and advantages of the present invention will become moreapparent to those persons having ordinary skill in the art to which thepresent invention pertains from the foregoing description taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of an internal valve of the presentinvention.

FIG. 2 is a cross-sectional view of the valve of FIG. 1 illustrated inits closed position and with the mounting flange thereof removed.

FIG. 3 is an enlarged cross-sectional view of an alternative fittingarrangement for the valve of FIG. 1.

FIG. 4 is an enlarged sectional view of an alternative of thepressurized chamber and plug of the valve of FIG. 1.

FIG. 5 is a side partially sectional view of another internal valve ofthe present invention illustrated in an open position.

FIG. 6 is a view of the valve of FIG. 5 illustrated in its closedposition.

FIG. 7 is an end partially sectional view of the valve of FIG. 5.

FIG. 8 is a sectional view of the upper portion of the valve of FIG. 7illustrating a variation thereof.

FIG. 9 is a cross-sectional view of another internal valve of thepresent invention.

FIG. 10 is a side sectional view of another valve of the presentinvention.

FIG. 11 is an enlarged view of the lower portion of the valve of FIG. 10illustrating the valve in an open position.

FIG. 12 is an enlarged view of the top portion of the valve of FIG. 10with the top shield portion thereof removed and a cap inserted therein.

FIG. 13a is a view of a valve similar to that of FIG. 10 showing theplug insert configuration and with the sealed volume outside thebellows.

FIG. 13b is a view similar to FIG. 13a showing the sealed volumepositioned inside the bellows.

FIG. 14 is a sectional view of a ball-type valve of the presentinvention illustrated in a closed position.

FIG. 15 is a view of the ball-type valve of FIG. 14 illustrated in anopen position.

FIG. 16 is a sectional view of a gate valve of the present inventionillustrated in the closed position.

FIG. 17 is a view of the gate valve of FIG. 16 illustrated in an openposition.

FIG. 18 is a partially sectional view of a rotary valve actuator systemof the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

Referring to FIGS. 1 and 2 an internal valve system of the presentinvention is illustrated generally at 40. Valve system 40 is mounted ina pressurized fluid containment vessel shown generally at 42 having avessel or shell wall 44 with the interior thereof filled with a(pressurized) fluid 46, such as hydrogen sulfide pressurized at fourhundred to five hundred pounds per square inch, for example. The vessel42 can be any transportation vessel such as a tank car, tank truck orcylinder.

The vessel outlet is illustrated generally at 48 and is closable by ablind flange 50, as shown in FIG. 1, secured to a mounting flange 52 ofthe shell wall 44 by bolt fasteners or cap screws 54 and with a suitablegasket 56 sandwiched therebetween. These fasteners 54 are threaded intotapped blind holes 58 in the mounting flange 52. The closing flange 50is applied for shipment purposes and is removed, as illustrated in FIG.2, for valve operation.

The mounting flange 52 is mounted flush with the exterior wall 44 of thepressure vessel 42 by means, for example, of a plurality of Allen headcap screws 60. This provides a desirable protective flush mounting ofthe mounting flange 52 to the exterior of the vessel 42 with a differentwrench configuration than is needed for the removal of the blind flange50 in accessing the valve discharge port. A gasket 64 between themounting flange 52 and the vessel wall 44 forms a seal therebetween. Byunscrewing the screws 60 the entire valve 40 can be easily removed fromthe vessel 42 for servicing, adjustment or replacement. This mountingarrangement also makes the installation of the valve 40 from outside ofthe vessel 42 relatively easy.

A valve seat 66 is threadably mounted into the flange outlet 68 and canbe unscrewed therefrom by means of a simple wrench and removed formaintenance purposes. The removable seat 66 is sealed to the mountingflange 52 by means of an O-ring system 70, or by adhesives, sealants, orgaskets. Alternatively, the seat 66 can be constructed as part of themounting flange 52 itself in which case it would not be a separatelyrenewable component.

A valve plug assembly shown generally at 72 includes a plug member 74formed of a replaceable resilient material configured to mate tightlywith the valve seat 66. The plug member 74 is removably mounted on asupport member 76, which is preferably metallic, and which provides asecondary, tight metal-to-metal contact around the circumference of theseat at location 78 in the event of the loss of or damage to the primaryresilient plug material. This sealing arrangement is best shown in FIG.2. This resilient material is selected to be compatible with the fluid46 to be contained in the vessel 42. In the case of hydrogen sulfidethis resilient material can be glass or carbon filled Teflon, forexample.

The plug assembly 74 is mounted upon or forms one end of a controlchamber 80. The sides of the control chamber 80 are formed by a bellowscylinder 82 which in turn is attached to the other end of the controlchamber 80. The ends of the bellows cylinder 82 are attached as bythreaded studs 84, 86 at the two ends of the chamber 80 and sealed byO-rings 88 and 90. Gasketed joints can be eliminated by forming theentire bellows-and-internal double acting cylinder assembly as a singlewelded construction. The chamber 80 is thus completely sealed from thefluids 46 of the vessel 42 and from the exterior of the vessel 42 exceptfor the communication provided by the control lines 92 and 94.

The bellows cylinder 82, which defines the walls of the control chamber80, can be of standard manufacture and its construction material shouldbe compatible with the fluid 46 of the vessel 42. Stainless steel is anexample of a possible compatible material. The bellows cylinder 82 willbe of a sufficient strength to withstand the internal pressure of thevessel 42 and of a sufficient length to allow for the movement of theplug assembly 72 over its full stroke length without undue fatigue evenafter tens of thousands of cycles. The bellows cylinder 82 is preferablyalways in compression to some extent and never in extension. Thisprevents "snaking" thereof which is a characteristic of bellows inextension. The bellows cylinder 82 in compression acts as a springbiasing the plug assembly 72 in a closed position as shown in FIG. 2.The spring rate of the bellows cylinder 82 can be selected to overcomethe forces exerted thereon by the fluid 46 in the vessel interior ifdesired.

Alternatively, the valve 40 can be designed to be in a normally "open"position by shortening the bellows cylinder 82 slightly or moving it aslight distance away from the valve seat 66. This, however, puts thebellows cylinder 82 in extension during closing, which is lessdesirable, as previously discussed. More preferably, the seat/plugconfiguration would be altered to allow the valve 40 to be open when thebellows cylinder 82 is relaxed and closed when compressed.

A rigid support cylinder 96 is securely welded to the mounting flange 52at its upper end and thereby rigidly connects the chamber 80 relative tothe vessel wall 44. The support cylinder 96 provides guiding andstabilizing functions and also protectively envelopes the criticalbellows cylinder 82. Contact wear between the bellows cylinder 82 andthe support cylinder 96 can be minimized by providing a Teflon sleeve 98within the support cylinder 96. The bellows cylinder 82 is mechanicallyfastened to the support cylinder 96 at the end opposite from the plugassembly 72 by any convenient fasteners such as studs and nuts 97. Thisfastening system is sealed by an O-ring 98 to an end mounting plate 99which is bolted by bolts 100 to the support cylinder 96. This mountingprovides for the control chamber 80 by fixing it at one end such thatthe linear expansion of the chamber 80 causes the movement of the plugassembly 72 towards and subsequently against the valve seat 66. Thesupport cylinder 96 is not a sealed unit however and passage for thefluid 46 of the vessel 42, as indicated by the arrows in FIG. 1, isprovided by ports 102 and 103 therethrough conveniently located at thetop (or bottom) of the support cylinder 96.

A standard double-acting piston assembly shown generally at 104 is usedin valve 40 and includes a cylinder or housing 106 defining a cavity108, a piston 110 slidable within the cavity and defining on oppositessides thereof first and second chambers 111, 112, and a piston rod 114secured at one end to the piston 110 and at the opposite end thereof tothe plug assembly 72, and passing through the housing 106 through apiston seal 115. The control lines 116 and 118 communicate with thechambers 111 and 112, respectively, and are controlled from outside ofthe vessel. This control is accomplished by means of applying apressurized fluid, as by means of a pump shown schematically in FIG. 2at 120, to one or both of the external hydraulic fittings 122, 124.These hydraulic fittings 122, 124 are shown offset for ease ofconvenient explanation but in the preferred design they are aligned intothe plane of FIGS. 1 and 2. The pump 120 therefore can pressurize onefitting 122 (or 124) while depressurizing the other fitting 124 (or122). The pump 120 supplies any suitable type of pressurized fluid, suchas hydraulic fluid, pressurized grease or pressurized gas.

The control lines 116, 118 pass through an elongated member 126 withinthe bellows cylinder 82 and which is threadably secured at its upper endto the housing 106 and at its lower end to mounting plate 99. Themounting plate 128 in turn is secured by bolts 100 to a cylinder flange128 welded by welds 136 and 138 to the outside and bottom, respectively,of the support cylinder 96. A suitable gasket 140 is sandwichedtherebetween to form a good seal.

An optional safety feature of this valve is illustrated in FIGS. 1 and2. A small connecting passage 142 is provided between one or both of thecontrol lines 92, 94 where they pass through the mounting flange 52 andthe blind flange stud hole 58. The stud 60 is replaced with a specialcap screw (see FIG. 3). When this cap screw is loosened or improperlytightened, fluid will escape past the gasket 139 at the bottom of thestud hole 58 causing the lines 92 or 94, if are pressurized, todepressurize. This allows the plug assembly 72 to move towards itsrelaxed position, which in the case of the valve design illustrated inthe drawings is its closed position.

Alternatively, two passages 142, 143, one from line 116 and the otherfrom line 118, can converge upon one (or more) of the stud holes 58 ofthe blind flange 52, as depicted in FIG. 3. Normally sealed from eachother and outside by a gasket 144 when the cap screw 146 is properlyapplied, the two passages 142 are connected together when the cap screw146 is loosened. This loosening allows the pressure in both chambers111, 112 of the double-acting piston assembly 104 to equalize andthereby allows the normally closed valve to move to its closed positionas the bellows cylinder 82 relaxes. The normally closed characteristicis determined by the length and spring rate of the bellows cylinder 82.In a normally closed configuration, the spring rate is selected toovercome the force exerted thereon by the maximum vessel workingpressure as effected by the fluid pressure through the ports 100, 102.

It may be desirable to provide by means outside of the vessel 42 for thedirect pressurization of the control chamber 80 with a pressurizedfluid, either a gas or liquid, from a pump shown schematically at 148.This arrangement is shown in FIG. 4 and can assist in the closing of thevalve plug assembly 72. It can provide a means of externally monitoringboth the integrity of the seal and the valve position. By selectingdifferent spring lengths and/or rates, a normally open valve mechanismwith a similarly configured valve, with or without optional separatesprings, as mentioned above can be constructed. If separate springs aredesired they can be placed inside of the control chamber 80, asillustrated in FIG. 4 at 150, to avoid exposure to the vessel fluid 46.

A positive closure of the plug assembly 72 is assisted by the pressurein the vessel itself. This closure is further assisted by thedouble-acting piston cylinder 104 which can be easily pressurized by theuser through lines 116, 118 to force the valve plug assembly 72 closedtightly against the valve seat 66. When the vessel 42 is atransportation vessel, the loading/unloading valve 40 would normally beso closed for transportation and left closed except when actually neededto gain access to the interior of the vessel.

The safety relief port(s), if any, of a transportation vessel or anyother pressure vessel, would typically be equipped with a normally openinternal valve and such valve would be left open except in unusualcircumstances wherein it is desirable to be able to completely isolate asafety release valve for repairs.

This valve 40 when properly installed on a pressure vessel 42 can beeasily removed from the vessel by trained personnel without entering thevessel. Only depressurization and suitable personal protective clothingneed be worn by the personnel if the valve 40 is mounted above theliquid level 151 in the vessel 42.

Furthermore, this valve 40 is fully protected from fire, impact, abuse,corrosion, weather and so forth by the shell of the vessel wall 44itself. All of the externally protruding parts, such as the hydraulicfittings 122, 124, the blind flange 52 and blind flange bolts 60 can beremoved, either accidently or intentionally, with the valve 40 in theclosed position, without losing any vessel fluid 46.

The valve 40 has no packing or other frictional seals to leak. Evenfailure of the substantial and external bellows seals, while unlikely ifproperly designed, does not result in either the valve 40 being renderedinoperable or in the vessel fluid 46 being lost to the environment.Failure of the bellows cylinder 82 results in the pressurization of thebellows control chamber 80 only, which tends according to the preferreddesign to close the plug assembly 72. The vessel contents must stillpass by the highly reliable piston 115, enter the cylinder or housing106, pass through the resident control fluid before arriving at thehydraulic fittings 122, 124. These fittings, when not in use, arepreferably sealed with caps 152, 154, as shown in FIG. 1. When in usethe fittings 122, 124 are connected to the high pressure pump 120 whichfurther makes leakage difficult. The fittings 122, 124 themselvespreferably contain automatic valves which prevent the flow of fluidexcept when connected to hydraulic pump lines. These multiple lines ofsecondary leakage defenses ensure that leakage through the controlmechanism is essentially impossible, which is a significant improvementover existing valves. This valve 40 can be remotely controlled easilyeither manually or automatically using standard control instrumentation.For example, the valve 40 can be easily made to close on excess flow,loss of line pressure, tank car movement, or in the event of fire ordownstream disruption.

Another valve of the present invention is illustrated in FIGS. 5-7generally at 160. Valve 160 similarly is designed to be contained withina fluid containment compartment of a pressure vessel shown generally at162. This vessel 162 typically is adapted to contain fluid 164, eithergas or liquid and usually under pressure, and can be a tank car, highwaytanker, stationary vessel, cylinder or the like. As illustrated in FIG.7, the valve comprises a valve body portion 166, a valve portion 168 andvalve actuation portion 170, as designated by the respective brackets inthat drawing. The preferably metal valve body portion 166 includes aninlet opening 172 and an outlet opening 174 positioned at the rear ofthe valve 160 through the flange 176. The flange 176 is bolted to thewall 178 of the vessel 162 by bolts 180. The flange 176 can be omittedand the valve 160 welded or otherwise suitably attached directly to theexit nozzle or piping leading to the exterior of the vessel 162.

The valve portion 168 defines a cavity 182 within the valve body portion166 and disposed between the inlet and the outlet openings to form apassage within the body portion 166. A valve member or plug 188 isdisposed adjacent to the cavity 182 and movably engageable with thesealing surface of the opening. The inlet opening 184 is preferablyprovided with a replaceable valve seat member 192.

The valve actuating portion 170 includes lower and upper body sections194 and 196. The lower body section 194 may, but need not, beconstructed of one piece with the valve body portion 162. Instead of abellows sealing element as was provided in the embodiments of FIGS. 1and 2, a diaphragm sealing element 198 is used for valve 160. Thediaphragm sealing element 198 must be flexible over at least a part ofthe surface thereof to a sufficient extent to allow for the operation ofthe valve over a useful service life without undue fatigue. The surfaces200 and 202 of the body sections 194 and 196, respectively, arepreferably shaped or molded to evenly conform to and completely supportthe diaphragm sealing element 198 at its two extremes of travel as isapparent from a comparison of FIGS. 5 and 6. The diaphragm sealingelement 198 is formed of a strong flexible material, such as metal (e.g.stainless steel), plastic or rubber, suitable for exposure to the fluid164 in the vessel 162 and to the control fluid. It is preferably of alaminated or multi-layered construction. The diaphragm sealing element198 is sealed between the body sections 194 and 196 with a gasketbetween itself and the body section 196. The body sections 194 and 196are held firmly together by any convenient means as by bolts 206.

The surfaces 208 and 210 of the body sections 194 and 196 are shaped tosupport and limit the movement of the piston or pressure plate 212 atits two intended extremes of travel, as is apparent from FIGS. 5 and 6.The pressure plate 212 is attached firmly to the diaphragm sealingelement 198 to form a gasketed seal, so that no fluid communication ispossible between the variable area upper and lower chambers 214, 216.The pressure plate 212 has an effective cross-sectional area in thechamber which is substantially greater than the cross-sectional area ofthe valve port area circumscribed by seat member 192.

One end of a connecting section 220 is firmly attached to or is a partof the piston assembly and includes a rod 222 passing through apassageway 224 in the body section 196 towards valve body passage 182.This passageway 224 is preferably aligned with the valve inlet opening172 of the valve body portion 162.

Connecting section 220 has one end thereof operatively connected to themovable valve member 224. Connecting section 220 preferably has a yokeportion 226 secured to the rod 222. The yoke portion 226 attaches at oneend to a movable valve section 224 as shown and at is opposite end tothe rod 222 which in turn is connected to the pressure plate 212.

Less advantageously, the connecting section 220 can connect directly tothe movable valve member 228 by passing through a seal (not shown) andinto and through chamber 182. If this direct connection is made, theseal used can be another bellows or diaphragm to minimize thepossibility of any leakage.

The application of force to the surface of the pressure plate 212 facingthe variable area chamber 228 is transmitted directly by connectingsection 220 to the movable valve section 224 and thereby to the plug 188causing the plug to move towards the extreme open position shown inFIGS. 5 and 7 as the volume of the chamber 182 increases towards itmaximum. The force can be applied to the pressure plate 212 by anyconvenient means through the upper passageway 230 in the body section196. The force preferably is applied by injecting a pressurized fluidfrom a pump as shown schematically in FIGS. 5 and 6 at 240. The pump 240can be a source of compressed gas or hydraulic fluid which is introducedinto chamber 228 through passage 230 in the connecting channel or tubing242 leading to the outside of the pressure vessel 162.

An alternative method of applying force to the pressure plate 212 isillustrated in FIG. 8. It is seen therein that the force is applied byapplying heat to a suitable fluid contained in the variable volumechamber 228 and/or passageway 230 causing thermal expansion andpressurization within the cavity or passage. The heat can be deliveredto the fluid by means of steam or suitably limited electric powerconducted to the actuator through one or more sealed conductors viachannel. In this manner a non-flexing, highly reliable secondary barrierto the inadvertent escape of vessel contents can be provided since thesecondary conductor tubes can readily be sealed from both the contentsof chamber and the exterior world and since the channel can also bereadily sealed from the outside environment. Such a system does notallow escape of the vessel contents even in the unlikely event ofdiaphragm failure or channel failure. Alternatively, and perhaps lessadvantageously, the force can be applied by means of a fixed or movable,solid push/pull rod or screw passing directly to the outside of thevessel through the passageway 230 and the channel 242. Alternatively,the passageway can contain an electrically-driven gear motor or solenoiddevice which applies force to the pressure plate 212 and is powered byconductors traveling through the channel 242 to the exterior of thevessel 162. The power sources and/or force applicators mentioned in thisparagraph are shown generically and schematically in FIG. 8 at 244. Itis also within the scope of this invention to provide a tension orcompression spring 245 in the chamber 228 to bias the pressure plate 212up or down, as desired.

When the valve 160 is to be moved to its open position as shown in FIGS.5 and 7, force is applied to the pressure plate 212 by any of the meansdescribed herein and preferably controlled from outside of the vessel162. This force causes a downward movement of the pressure plate 212,the connecting section 220 and the movable valve section 226 and theplug 188, thereby opening up inlet opening 172 and allowing the vesselfluids to flow unimpeded through the valve and outlet piping of thevessel 162. When the valve 160 is to be closed or moved to its positionas shown in FIG. 6, the applied force is removed. The vessel pressure isexerted through closing passages 243 and 244 against the underside ofthe pressure plate 212, the diaphragm sealing element 198 and alsoagainst the valve portion causing the valve portion, the connectingsection 220 and the piston 222 to move towards the opposite extremeposition (the up or raised position as shown in FIG. 6), therebydiminishing the size of the variable volume chamber 228. This movementcloses the valve 160. If the pressure in the vessel 162 is insufficientto close the valve 160 under anticipated conditions, then a spring 222as shown in FIG. 8 can be used to assist in the closure process. Thisspring 222 preferably is placed within the chamber 228 (and passage230), operatively connected to the piston 212 and connecting section 222but still protected by the diaphragm sealing element 198 from anycontact with the fluid in the vessel 162.

The configuration of the valve 160 as illustrated in the drawings isnormally closed. It is also within the scope of the present inventionhowever to modify this valve so that it is normally open by a number ofsimply modifications in the relationship of the plug to the seat and theactuator to the valve. Further, the valve 160 illustrated in FIGS. 5-7is not intended to be removable from the outside of the vessel 162, incontrast to the valve 40 illustrated in FIGS. 1 and 2. Rather it must beinstalled and serviced by actually entering the vessel 162.

Referring to FIG. 9 another valve design of the present invention isillustrated generally at 250. The sealing section of the valve actuatorportion of this valve 250 differs from the sealing section of the valveactuating portion of the valve 160 in FIGS. 5-7 in that a bellows 252 isutilized instead of a diaphragm sealing element 182. This valve 250 issimilarly intended for installation within the envelope of a pressurevessel.

In use, pressure from the contained vessel fluid 254 (gas or liquid)flows around the rod member 256 into the cavity 258 within the bellows252 and against the underside of the piston or pressure plate 260mounted on top of the rod member 256. The top of the bellows 252 isaffixed and sealed to the pressure plate 260. A pressure cavity 262 isformed by the body 264 of the actuator, the bellows 252 and the pressureplate 260. The bellows 252 is affixed and sealed at its bottom end tothe body 264, and the other bellows end and the pressure plate 260 arefree to move up and down in the sealed cavity 262. There is no fluidcommunication between the cavity 262 and interior of pressure vesselwhich contains this valve 250. The body portion 264 can be made in onepiece or preferably, as shown, as an assembly comprising two or morepieces 268, 270 connected by bolts 272, 274 through their flanges 276,278 and sealed by gasket 280 sandwiched therebetween.

The bellows 252 is preferably selected so that its fully relaxed lengthis no shorter that the length of the interior of the cavity 262 suchthat the bellows is always at least somewhat compressed in lengthregardless of the position of the pressure plate 260 within the cavity.This minimizes any natural "snaking" or distortion characteristic of thebellows in extension when exposed to higher internal and externalpressure. Furthermore, in order to insure and maintain the correctalignment of all of the corrugations of the bellows 252 duringoperation, spacer washers or rings 284 can be positioned in the groovesbetween the corrugations.

The neutral or relaxed position of this actuator of the valve 250 ofFIG. 9 is with the pressure plate 260 at the top of the cavity 262 beingheld there by the natural spring action of the bellows 252 and by thepressure of the internal vessel fluid 254, as previously described.Pressurized control fluid from a pressure source as shown schematicallyat 286 is introduced into the cavity 262 from outside of the vessel viaconduit 288. This pressurized control fluid overcomes the natural springcharacteristic of the bellows 252 and the internal pressure of thevessel fluid 254 exerted on the inside of the bellows 252 and againstthe bottom surface of the pressure plate 260 and moves the plate towardsthe bottom of the cavity 262 thereby compressing the bellows 252. Theconnecting rod member 256 which is attached to the piston 260 on theinside of the bellows 252 transmits force and linear movement to a valveassembly (not shown in FIG. 9) which can be similar to the valve sectionof FIGS. 6-8, for example. If attached in place of the actuator portionof FIG. 2, this actuator would produce a normally closed valve designwith or without the assistance of vessel pressure and/or springs. Anormally open configuration can also be readily produced as would beapparent to one skilled in art.

Normally open and closed versions of the externally removable valveapparatus described in FIG. 1, for example, can also be readilyconstructed using this simpler form of the bellows actuator rather thanthe more positive bellows sealed double-acting cylinder arrangementillustrated in FIG. 1. The valve 250 of FIG. 9 form of actuator dependsupon spring action, either from the bellows 252 itself or from separateassisting springs, and/or the internal pressure of the vessel to move itto one of its two extreme positions. This is in contrast to the doubleacting cylinder 104 described and illustrated in FIG. 1 which can bemoved positively to either position by means of external pressure ifdesired.

Any other suitable means of applying the force, including any of thevarious alternative means of applying force to the piston 212 of FIGS.6-8 (the diaphragm sealed actuator embodiment), can be readily used toapply force to the piston of the bellows actuator in FIG. 9 with similarresults.

A gate valve apparatus of the present invention is illustrated generallyat 300 in FIGS. 10 and 12. This apparatus 300 has a valve actuatingportion that includes a flexible sealing section, such as a bellows 306,or sufficient flexible length to allow for a long cycle life withoutfatigue failure, positioned within a tube 307. A piston or pressureplate 308 is positioned at the lower end of the bellows 306, and fluid310 in the pressure vessel bears against the outside of the bellows 306,rather than the inside thereof as in the valve 250 of FIG. 9. The upperend of the bellows 306 is attached and sealed to the wall of the vesselcontaining this valve 300 thereby creating a chamber 314 inside of thebellows 306 which is isolated from the fluid 310 of the vessel and whichcan be isolated also from contact with the external world if desired.

The downward force applied to the pressure plate 308 from within thechamber 314 can overcome forces such as the pressure of the fluid 310 orthe spring forces from the optional internal biasing spring 316, whichcan tend to compress the bellows 306 and cause the pressure plate 308 tomove away from the wall 317 of the vessel. This piston motion moves thegate valve member 318 which is operatively affixed to the end of thepiston into engagement with a seating section 320 of the valve, as bestshown in FIG. 10.

Removal of this downward force and/or application of an upward force onthe pressure plate 308 causes the bellows 306 to compress and thepressure plate 308 to move upwards towards the wall 317 of the vesseland thereby opening the gate valve member 318; this open position isillustrated in FIG. 11. The externally applied force can be applied, ineither direction, to the pressure plate 308 by means of an optionalconnecting member 322 passing between the pressure plate 308 and theexterior through the chamber 314 within the bellows 306 and to the wall317 of the vessel. A simple hand-operated screw jack, as shown in FIG.10 at 324, can be used to develop the upward or downward force asdesired and applied to the connecting member 322 and to the pressureplate 308. Preferably, all portions of the hand-operated screw jack 324protruding beyond the wall 317 of the vessel 312 can be removed prior toshipment or when not in use. The passage through the vessel wall 317into the chamber 314 of the bellows 306 can then be sealed with apreferably flush mounting plug when not in use, as shown in FIG. 12 at328. A seal can be positioned on or within the wall of the vessel 312 onthe connecting member 322 to further protect against the inadvertentescape of vessel fluid 310 should the sealing bellows 306 fail.

A housing, as shown in FIG. 10 at 332, positioned outside of the vessel312 can be provided, and an alternative force applying means, as shownschematically at 334 in FIG. 13, such as a solenoid, a motor, or adouble acting cylinder, situated within this housing. Alternatively,this force applying means 334 can be positioned on the interior side ofthe vessel wall, or within the chamber 314 formed by the seal of thebellows 306. This alternate force applying means 334 can be operativelyconnected to the pressure plate 308 by way of the connecting member 322.

It is also within the scope of this invention for the connecting member322 to comprise little more than an internal bellows guide within thebellows chamber 314 and an operating force applied by simplypressurizing or depressurizing the bellows chamber 314 with a fluid,such as a compressed gas or hydraulic fluid, from a pressure sourcedepicted schematically at 336 in FIG. 13 passing through an opening inthe vessel wall 317 from a control position outside of the vessel. Inthis embodiment, the external pressure supplied from pressure source 336tends to extend the bellows 306 and chamber 314 and the vessel pressureand/or biasing spring 316 would tend to compress or shorten the bellowschamber 314. The biasing spring 316 can be positioned within the bellowschamber 314 completely separated from the vessel fluid 310.

Suitable firm stops can also be provided on the bellows and diaphragmseals to prevent travel beyond the needed or intended limits to therebyprevent unnecessary damage or wear to these flexible seals.

Designs of the valve portions of the valves of the present invention inaddition to the valve portions previously described can be used invalves of the present invention, and examples thereof are shown in FIGS.14-17.

Referring to FIGS. 14 and 15 another valve apparatus of the presentinvention is shown generally at 344 and it includes a rotatable valveelement such as a plug or ball 346 that is rotatable in a cavity 348.The valve ball 346 is rotated by longitudinally moving an elongated rodmember 350. A linking lever member 352 is pivotally connected at one endto the ball 346 and pivotally connected at another point to theelongated rod member 350. Upward movement of the connecting rod member350 produced by a suitable actuator mechanism draws the linking levermember 352 upward to rotate the ball 346 into a closed position, asshown in FIG. 14. This actuator mechanism can, for example, be thatdescribed or illustrated in FIG. 9. When in the closed position, thepassageway 354 through the ball 346 is perpendicular to the passageway356 of the valve support structure 358. Moving the connecting rod member350 downward, as shown in FIG. 15, moves the linking lever member 352downward as well and thereby rotates the ball 346 into the open positionwherein the ball passageway 354 is aligned with the passageway 356through the valve support structure 358. In lieu of the ballconfiguration any other suitable type of rotating element, such as adisc, can be used.

FIGS. 16 and 17 illustrate an alternative valve apparatus as showngenerally at 360 which includes a sliding valve element 362. The slidingvalve element 362 is moved vertically with respect to a cavity 364formed in a cavity forming structure 366 between a closed position asillustrated in FIG. 16 and an open position as illustrated in FIG. 17.This movement is effected by vertically moving a rod or connectingmember 368 which is operatively attached to a suitable internalactuator, such as is shown in FIG. 9. FIG. 16 also shows a thickenedboss 370 welded into the shell 372 of the vessel. This integral boss 370can be used for mounting and attaching the internal valve apparatus tothe vessel instead of the flange system as shown for example in FIGS. 1and 5.

The valve designs described herein satisfactorily address the problemsof vulnerability, thereby making the valve as reliable and immune todamage as is the containment vessel to which it attached by theplacement thereof within the vessel walls and by providing externalcontrol functions. The natural shielding of the vessel shell walleliminates the need for additional heavy shielding for the valve. Also,the probability of physical abuse by a workman or by vandals isminimized since this valve is mounted within the protective envelope ofthe vessel.

The flexible (diaphragm or bellows) seals of these nozzles eliminate theneed for packing glands or other seals with rubbing surfaces and therebyremedy the problem of seal and packing gland leakage which isparticularly important when dealing with hazardous and/or obnoxioussubstances. A highly reliable secondary seal is also provided andprotects against the failure of the primary seal as a part of theactuator movement system.

The valves of the present invention can be readily configured to providea fail closed operation independent of the vessel pressure, flow rateand downstream pressure. This eliminates the need for valves on process,storage and transportation vessels which automatically close when nodemand for field delivery is being made, as during process shutdown oractual transportation. Further, the valve can be readily configured toprovide a fail open, or hold last position characteristics, as needed,for example on process vessels or safety release vents. The valvedesigns of this invention can be activated by remote controls, automaticcontrols, or manual controls. They further can be adapted to be poweredby human muscle, pressurized fluid, vacuum, electricity, heat,electromagnetic force, and/or pressure of the product contained in thevessel system itself.

The valve devices described herein thus are designed to be installedcompletely within the protective envelope of their pressure chambers andyet to be completely controllable from outside of the pressure vessel.The designs thereof need not and do not permit any trace leakage of thecontained material to the outside of the vessel through the controlmechanism communicating with the outside. By installing the entire valvemechanism and actuator totally within the protective envelope of thevessel the valve and actuator system is made as immune to damage byexternal causes as the vessel itself is.

In summary, the valve actuator consists in essence of an impermeableseal, preferably metal, sufficient in strength to withstand both theinternal and external pressures which may be applied to it, and having asufficient and flexible area to withstand without undue fatigue thenormal flexure movement of the valve. This seal can take the form of abellows or a diaphragm. The seal is arranged so that it always forms animpenetrable barrier to the passage of (fluid) material from the vesselto the control chamber and vice versa. The seal can be attached by anyconvenient means, such as a stem or ratchet system, to the valve plug orport in such a way that motion of the seal is transferred to the valveplug or port to open or close the valve. The connecting system can, butneed not, provide a mechanical advantage to amplify the force oramplitude of the moving seal or to convert its linear motion into rotarymotion, as by a rack and pinion gear drive, a ratchet, a lever or ahydraulic system.

The motion is imparted to the system by the use of pressure (or vacuum)or force applied to the control chamber outside of the seal in order tomove the seal to another position. This force can be supplied bydirectly introducing a pressurized control fluid into the controlchamber from the outside or by means of a direct mechanical linkage orcontrol rod to the outside or preferably by means of a hydrauliccylinder and piston arrangement or electric gear motor arrangementcontained entirely within the control chamber and pressurized orenergized from the outside via suitable port(s). The bellows, which isof a multi-ply design, used for the seal in high pressure applications.The diaphragm, which is also preferably multi-ply, can be used as theseal in low pressure applications at a somewhat lower cost. The seal isprotected from over extension by the design of the apparatus by means ofpositive stops. The actuator mechanism can be placed at any convenientpoint in the system, preferably entirely within the envelope of thevessel. The entire actuator mechanism and valve mechanism (if separate)can be removed from the vessel system as for maintenance withoutpersonnel entering the vessel. The mechanism is attached to the vesselin such a way that no essential part protrudes beyond the vesselenvelope so as to provide a point of purchase for striking objects. Thiscan be accomplished by means of a flush mounting flanges, cover platesor by mounting the mechanism entirely within the vessel or within theinternal piping of the vessel.

The device is designed preferably so that in its non-energized orrelaxed state it is positively closed or open as is appropriate for theparticular vessel nozzle. The internal pressure of the containmentvessel tends to maintain the valve in its deenergized position. Positiveshut off (or opening if desired) of the valve, regardless or whether ornot the internal pressure is high, low or even negative, can beprovided. Notwithstanding the above however, the device can be designedinstead to maintain, once deenergized, what ever position the valve waslast in, if needed.

The valve and/or actuator devices herein can be used with other safetysystems including safety relief valves and internal excess flow valves,so as to for example provide an externally adjustable internal excessflow valve. Similarly, the valve system can be applied to the reliefvalve system so that the flow of material to the relief valve can beexternally controlled, as for maintenance purposes. It is further withinthe scope of this invention to provide a remotely adjustable pressurerelief valve for the fluid containment vessel.

The system of this invention which includes a vessel, an actuatormechanism and valve members can be manufactured from a wide variety ofmaterials including metals, plastic, polymers, vitreous materials,combinations thereof, and especially heat and corrosion resistantmaterials such as stainless steels. The specific material or materialsselected, as well as their form, depend in part on the chemicals beingcontained or transported in the vessel and the anticipated conditions ofservice. Careful considerations should be given in the design to usematerials compatible with the environment to which they will be exposed.

The operative force mechanism must have sufficient design power toovercome the opposing internal and/or external pressures, the springresistance of the seal, which is often substantial, and the ordinarybinding and frictional forces of the entire mechanism. Additionally, thedesign should take advantage of and provide for large flexing surfaceson the sealing device (the bellows or the diaphragm) so that no segmentof the flexing surface thereof is stressed to fatigue or permanentdistortion. This allows the seal to have a nearly indefinite life.

It will be readily apparent to those skilled in the art that manymodifications can be made to this valve design and fall within the scopeof this invention. For example, the size, configuration and arrangementof the components can be changed to meet specific requirements. Theconnecting section can include one or more pivoting links or can becoupled to a rack and pinion gear device or to another hydraulic device,for example, to facilitate the operation, achieve a mechanicaltransformation or advantage, or simply to better fit into the availablespace. Also, soft valve components can be readily used in the relativelyprotected environs of the vessel interior and this internal placement issafer than the external usage of soft valve components. The valve canthereby have an extremely tight valve shutoff. The available force ofthe actuator can be used to tightly shut off the valve with hard(metal-to-metal or ceramic) valve seats as well if desired. Additionallyan assortment of compression and/or tension springs can be used, asneeded, to facilitate the operation of the actuator apparatus.

While this valve apparatus is primarily intended to be installed withinthe protective envelope of pressure vessels to form an improved materialcontainment system, there are obvious advantages to this valve designindependent of its interior installation aspect, as would be apparent tothose skilled in the art.

A system for controlling rotary elements within pressure vessels isshown generally at 400 in FIG. 18. The system 400 is controlled fromoutside of the wall 402 of the pressure vessel shown generally at 404 bya pump or other control system shown schematically at 406. It isparticularly suited for rotating internal valves as shown generally andschematically at 408. The system 400 is to be mounted within the fluidvessel 404 and to a mounting plate 410 near the wall 402 of the vesselseparating the vessel's interior from its exterior.

This system 400 includes a sealed control chamber assembly showngenerally at 412 sealing therein a double acting cylinder showngenerally at 413. The double acting cylinder 413 when reciprocatedpushes the teeth 414 of a ratchet wheel or spur gear 416 through aconnecting or ratchet member 418. The ratchet wheel 416 in turn rotatesthrough a drive shaft 419 the rotatable element or valve 408 to which itis keyed and which is positioned on the opposite side of the mountingplate 410. The ratchet wheel 416 contains a number of teeth 414preferably evenly divisible by four when the rotary element 408 is aquarter-turn rotary element, such as a ball, plug or disc valve.

The sealed control chamber assembly 412 includes a sealing bellows 420of sufficient strength to withstand the fluid pressure in the vessel 404and of sufficient length and flexibility to allow for the operation overthe full stroke length of the double acting cylinder 413 without unduefatigue and over a long and useful life. The sealing bellows 420 sealsthe interior cavity 422 of the control chamber assembly 412 from fluidcommunication with the interior of the vessel 404. The sealed controlchamber assembly 412 is preferably mounted about a pivot point 424 ofthe mounting plate 410 at the end most distance from the ratchet wheel416. The sealed control chamber assembly 412 is shown closed at bothends by flange 426 at the ratchet wheel end and flange 428 at the pivotend, both flanges being welded to the bellows 420.

The double acting cylinder 413 includes a cylinder or housing 436 whosecylindrical wall is preferably only slightly smaller than the insidediameter of the bellows 420. The stroke of the double acting cylinder413 is preferably short, sized to be just sufficient to move the ratchetwheel 416 forward one tooth per cylinder stroke. The shorter the strokethe less resulting fatigue wear and distortion on the bellows 420. Thestroke length can be limited, if desired, by an internal travel stopblock. The double acting cylinder 413 also guides and supports thereciprocable bellows 420.

Alternatively, the sealed control chamber assembly 412 can be rigidlymounted at the pivot point 424, as shown in FIG. 19, and the cylinder413 itself pivoted within the cavity 422 at the end most distant fromthe ratchet wheel 416. In this design the bellows 420 itself absorbs theslight sideways bending flexure which occurs with each stroke of thedouble acting cylinder 413 against the ratchet wheel 416. In this case,the control lines 438 and 440 external to the sealed control chamberassembly 413 can be rigid. This is in contrast to the preferredembodiment wherein (FIG. 18) the lines must be slightly flexible.

The piston rod 441 of the double acting cylinder 413 is coupled rigidlyor flexibly as needed to the inner surface of the forward flange 426 andpreferably aligned with the ratchet member 418 which similarly can becoupled rigidly or flexibly to the exterior surface of the forwardflange 426. The control passages 446, 448 communicate the sealed controlchamber assembly 412 through the control lines 438, 440, respectively,with the control ports or fittings 450, 452, respectively, at the vesselwall 402. The pumping system or pump 406 then can be removably coupledto the fittings 450 and 452. The control passages 446, 448 extendthrough the elongated connector member 454 to the two sides of chambers456, 458, respectively, of the housing 436 of the double acting cylinder413. The connector member 454 has opposite, threaded connector ends 460and 462 which are screwed into corresponding threaded openings in thehousing 436 and the rearward flange 428, respectively.

A spring 463 (or equivalent biasing means) is secured to the mountingplate 410 at one end thereof and attached to either the sealed controlchamber assembly 412 (FIG. 18) or to the ratchet member 418 (FIG. 19)such that the ratchet member is biased against the ratchet wheel 416. A"dog" or ratchet pawl 464 is pivotably secured to the mounting plate 410and is held against the ratchet wheel 416 by the spring 466 or otherbiasing means. This spring 466 is secured at its opposite end to themounting plate 410. The pawl 464 prevents the reverse rotation of theratchet wheel 416 and thereby of the rotary element 408.

Magnets 468 can be mounted on the ratchet wheel 416 and a magneticallytransparent blind ended tube 470 positioned so that the magnets 468 passunder it as the ratchet wheel 416 rotates. A magnetic field sensor shownschematically at 471, such as a reed switch, a sensing magnet, or coil,detects the magnets 468 as they pass under the tube 470. Thisarrangement allows for the sensing of the rotary position of the shaft419, and therefore of the rotary element 408, from outside of the vessel404. It can also drive a counting device 471a (FIG. 1a) to record therevolutions of the shaft 419 which could just as readily be driving apositive displacement pump.

The double-acting cylinder 413 is operated by alternately pressurizingand depressurizing the control ports or fittings 450, 452 by the pump406 with a fluid such as hydraulic fluid or compressed gas. By applyingpressure to fitting 452 while depressurizing fitting 450 the pistonplate 472 is moved towards the pivot point 424, retracting the controlchamber assembly 412 and pulling the ratchet member 418 back to engagewith the next tooth 414 of the ratchet wheel 416. When the retraction issufficient, that is at the bottom of the stroke, the force from thespring 463 pulls the ratchet member 418 into engagement with the nexttooth 414 of the ratchet wheel 416. By applying pressure to the fitting450 and depressurizing the other fitting 452 the piston plate 472reverses its travel direction and moves away from the pivot point 424.This movement extends the chamber assembly 412 and the ratchet member418, which is engaged with a tooth 414 of the ratchet wheel 416, andthereby forces the engaged tooth forward, rotating the ratchet wheel 416slightly. The pawl 464 pivots and latches each tooth as it goes therebypreventing reverse rotation of the ratchet wheel 416. By repeating thisprocedure, the system can be made to rotate the drive shaft 419 and theconnected rotating or rotary element 408 in one rotation direction. Theprocedure can be readily carried out by an external double acting pumpcylinder (manually or automatically) or by an external series ofswitching valves controlled mechanically, manually or automatically.

The position of the rotary element 408 can be readily determined fromoutside of the vessel 404 as previously described. The rotation stopspositively whenever the reciprocating procedure stops, thereby holdingthe rotary element 408 at its last position. This can be an advantage insome control situations.

Also, if the seal of the bellows 420 fails there is no resulting leakagepast the highly reliable seal 474 of the double-acting cylinder 413, noris the system thereby rendered inoperable. Other sealed actuatordevices, such as those illustrated herein in FIGS. 5-10, can besubstituted with similar results, if desired.

The actuator force can be used to achieve a relatively tight valveshutoff with hard (metal-to-metal or ceramic) valve seats as well. Anassortment of compression and/or tension springs can be used tofacilitate the operation of the actuator system under specialconditions. Further, the actuator can be used to power or manipulateother devices within sealed vessels or enclosures, such as pumps,compressors, mixers, metering devices and the like. While this actuatoris primarily intended for installation within the protective envelope ofa pressure vessel, such as that designated by reference numeral 404, todefine a better material containment system, there are obviousadvantages to this valve and actuator assembly independent of aninterior installation.

This actuator design, using a bellows or similar flexible element, canbe readily adapted for use outside of a vessel. Its all metal, totallysealed design provides greatly improved protection for actuators, suchas that designated by reference numeral 408, in adverse environmentsexterior to vessels, such as under water, in corrosive environments, inouter space, in vacuums, and in extraordinarily dirty or abrasiveenvironments. Its design is intrinsically able to withstand higherpressures and temperatures than conventional actuators can withstand.

The forces available from this actuator design make all metalconstruction thereof possible. The actuator need not use conventionalflexible materials such as rubber, chlorofluorocarbons, plastics,fibrous materials, polymers and so forth. It also need not incorporate adouble acting cylinder using O-rings for it to function. Additionally,it need not use gaskets or O-rings if properly assembled or if weldedafter assembly. Its force output however can be large enough to producedeforming or sealing pressures on valve elements of all metalconstruction thereby achieving a highly reliable fire safe valve and/ora valve adaptable for extreme conditions of environment incompatiblewith the soft materials typically used for valve sealing. Additionally,since no packing glands are required, there are no attendant packinggland problems.

From the foregoing detailed description, it will be evident that thereare a number of changes, adaptations, and modifications of the presentinvention which come within the province of those skilled in the art.However, it is intended that all such variations not departing from thespirit of the invention be considered as within the scope thereof aslimited solely by the claims appended hereto.

What is claimed is:
 1. An actuator system comprising:a pressure vesselfor containing pressure fluid; a rotatable element positioned in saidpressure vessel; a ratchet wheel connected to said rotatable element forcontrollably rotating said rotatable element; a ratchet memberengageable with said ratchet wheel; reciprocating means positioned atleast partially within said pressure vessel and controllable fromoutside of said pressure vessel for reciprocating said ratchet memberrelative to said ratchet wheel to controllably rotate said ratchet wheeland thereby said rotatable element; and a sealed chamber assemblydisposed in said pressure vessel and within which at least a portion ofsaid reciprocating means is positioned for protection from pressurefluid in said pressure vessel.
 2. The actuator system of claim 1 furthercomprising biasing means for biasing said ratchet member against saidratchet wheel.
 3. The actuator system of claim 2 wherein said biasingmeans is attached directly at one end thereof to said sealed chamberassembly.
 4. The actuator system of claim 2 wherein said biasing meansis directly connected at one end thereof to said ratchet member.
 5. Theactuator system of claim 2 wherein said biasing means pivots saidratchet member about a pivot axis and said ratchet wheel is rotatableabout a rotation axis fixed relative to the pivot axis.
 6. The actuatorsystem of claim 2 wherein said biasing means comprises a spring.
 7. Theactuator system of claim 6 further comprising a mounting platepositioned in said pressure vessel, to which an end of said spring issecured and about which said reciprocating means is pivotable.
 8. Theactuator system of claim 7 wherein said ratchet wheel is rotatable aboutan axis passing perpendicularly through said mounting plate.
 9. Theactuator system of claim 8 wherein said rotatable element is secured toa side of said mounting plate opposite to said ratchet wheel.
 10. Theactuator system of claim 1 further comprising ratchet pawl means forpreventing reverse rotation of said ratchet wheel and thereby of saidrotatable element.
 11. The actuator system of claim 10 wherein saidratchet pawl means includes a pivotal ratchet member and biasing meansfor biasing said pivotal ratchet member against said ratchet wheel. 12.The actuator system of claim 11 wherein said biasing means comprises aspring attached at one end to said pivotal ratchet member.
 13. Theactuator system of claim 1 wherein said pressure vessel includes apressure vessel wall separating the interior of said pressure vesselfrom the exterior, and further comprising a mounting structure mountedto said pressure vessel wall and to which said ratchet wheel and saidreciprocating means are attached.
 14. The actuator system of claim 1wherein said rotatable element comprises a valve.
 15. The actuatorsystem of claim 14 wherein said valve is selected from the group ofball, plug and disc valves.
 16. The actuator system of claim 1 whereinsaid ratchet wheel includes about its entire circumference a pluralityof spur gear teeth.
 17. The actuator system of claim 16 wherein saidrotatable element comprises a quarter-turn rotatable element and thetotal number of said spur gear teeth disposed about the entirecircumference of said ratchet wheel is evenly divisible by four.
 18. Theactuator system of claim 1 wherein said sealed chamber assemblycomprises an interior cavity and sealing bellows means for sealing saidinterior cavity from pressurized fluid in said pressure vessel.
 19. Theactuator system of claim 1 wherein said sealed chamber assembly includesan assembly end disposed away from said ratchet wheel, and said sealedchamber assembly is pivotally attached to a structure fixed relative tosaid pressure vessel at said assembly end.
 20. The actuator system ofclaim 1 wherein said sealed chamber assembly comprises a variable lengthsealed chamber assembly whose end distant from said ratchet wheel isrigidly fixed relative to said pressure vessel.
 21. The actuator systemof claim 1 wherein said reciprocating means includes a piston-cylinderarrangement positioned inside of said sealed chamber assembly andpressurizing means for pressurizing said piston-cylinder arrangement.22. The actuator system of claim 21 wherein said sealed chamber assemblyincludes an elongated bellows in which said piston-cylinder arrangementis positioned and a pair of flanges at opposite ends of said elongatedbellows and to which said elongated bellows is secured.
 23. The actuatorsystem of claim 22 wherein said ratchet member is rigidly coupled at itsrearward end to said forward flange.
 24. The actuator system of claim 22wherein said ratchet member is connected to the forward of said flanges.25. The actuator system of claim 22 wherein said piston-cylinderarrangement includes a piston rod connected at an outer end thereof tothe forward of said flanges.
 26. The actuator system of claim 25 whereinsaid piston rod has its longitudinal axis aligned with the longitudinalaxis of said ratchet member.
 27. The actuator system of claim 25 whereinsaid piston rod is rigidly coupled at its forward end to said forwardflange.
 28. The actuator system of claim 25 wherein said piston rod isflexibly coupled at its forward end to said forward flange.
 29. Theactuator system of claim 21 wherein said piston-cylinder arrangement ispivotal within and relative to said sealed chamber assembly.
 30. Theactuator system of claim 21 wherein said piston-cylinder arrangement isfixed within and relative to a longitudinal axis of said sealed chamberassembly, and said sealed chamber assembly and said piston-cylinderarrangement therewithin are pivotal about an axis fixed relative to saidratchet wheel.
 31. The actuator system of claim 21 wherein saidpiston-cylinder arrangement includes a double-acting cylinder positionedentirely within said sealed chamber assembly.
 32. The actuator system ofclaim 21 wherein said piston-cylinder arrangement includes a housinghaving an opening and a seal disposed in said opening and through whichsaid piston rod passes.
 33. The actuator system of claim 21 wherein saidpressurizing means is positioned outside of said pressure vessel. 34.The actuator system of claim 33 wherein said pressure vessel includes apressure vessel wall separating the interior from the exterior of saidpressure vessel, and said reciprocating means includes control portspositioned at said pressure vessel wall and communicable with saidpressurizing means.
 35. The actuator system of claim 34 wherein saidreciprocating means includes flexible tubing communicating one end ofsaid sealed chamber assembly with said control ports.
 36. The actuatorsystem of claim 35 further comprising biasing means for biasing saidratchet member against said ratchet wheel and about a pivot axis, saidbiasing means causing said one end to pivot about said pivot axis. 37.The actuator system of claim 34 wherein said reciprocating meansincludes a rigid tubing connecting at one end thereof with said sealedchamber assembly and at the other end thereof with one of said controlports.
 38. The actuator system of claim 1 further comprising sensingmeans for sensing from outside of said pressure vessel the position ofsaid rotatable element as controlled by said ratchet wheel.
 39. Theactuator system of claim 38 wherein said sensing means comprises amagnetic field sensor and at least one magnet mounted on said ratchetwheel.
 40. The actuator system of claim 39 wherein said magnetic fieldsensor is selected from the group of a reed switch, a sensing magnet anda coil.
 41. The actuator system of claim 1 further comprising countingmeans for counting the revolutions of said ratchet wheel.
 42. Theactuator system of claim 1 wherein said ratchet wheel includes aperpendicular shaft to which said rotatable element is secured.
 43. Anactuator system for controllably rotating a rotatable element in apressure fluid vessel, said actuator system comprising:a ratchet wheelconnectable to a rotatable element positioned in a pressure fluid vesselfor rotating the rotatable element; a ratchet member engageable with andbiased towards said ratchet wheel; mounting means for mounting saidrotatable wheel and said ratchet member inside of the pressure fluidvessel and generally adjacent to the rotatable element; piston-cylinderreciprocating means for reciprocating said ratchet member relative tosaid ratchet wheel to controllably rotate said ratchet wheel and therebythe rotatable element; and a sealed chamber assembly within which atleast a portion of said piston-cylinder reciprocating means ispositioned for protection from pressure fluid in the pressure fluidvessel when said reciprocating means is mounted therein by said mountingmeans.
 44. The actuator system of claim 43 wherein said mounting meanscomprises a mounting plate securable to a wall of the pressure fluidvessel and to which said sealed chamber assembly is secured.
 45. Theactuator system of claim 43 wherein said piston-cylinder reciprocatingmeans is attached to said mounting means and is thereby positionable atleast partially within the pressure fluid vessel.
 46. The actuatorsystem of claim 43 wherein said ratchet wheel includes a perpendicularshaft drivingly connectable to the rotatable element.
 47. The actuatorsystem of claim 43 wherein said piston-cylinder reciprocating meansincludes a double-acting cylinder positioned within said sealed chamberassembly and pressurizing means positionable outside of the pressurefluid vessel for controllably pressurizing said double-acting cylinderwhen positioned in the pressure fluid vessel.
 48. An actuator system forcontrollably rotating a rotatable element, said actuator systemcomprising:a ratchet wheel connectable to a rotatable element forrotating the rotatable element; a ratchet member engageable with andbiased towards said ratchet wheel; reciprocating means for reciprocatingsaid ratchet member relative to said ratchet wheel to controllablyrotate said ratchet wheel and thereby the rotatable element, saidreciprocating means including a double-acting piston; and a protectivesealed flexible bellows chamber assembly within which said double-actingpiston is positioned; wherein said reciprocating means includespressurizing means positioned outside of said protective sealed flexiblebellows chamber assembly for pressurizing said double-acting piston. 49.The actuator system of claim 48 wherein said elongated flexible bellowsis guided and supported by said double-acting piston and flexiblycontracts and expands with the reciprocation of said double-actingpiston.
 50. The actuator system of claim 48 further comprising a driveshaft drivingly connecting said ratchet wheel to the rotatable element.51. The actuator system of claim 48 wherein said protective sealedchamber assembly comprises a bellows assembly defining at least in parta cavity in which said double-acting piston is protectively enclosed.52. The actuator system of claim 51 wherein said bellows assemblyincludes an elongated flexible bellows disposed about said double-actingpiston.
 53. The actuator system of claim 52 wherein said bellowsassembly includes a pair of flanges at opposite ends of said elongatedflexible bellows and to which said elongated flexible bellows is securedat opposite ends thereof.
 54. The actuator system of claim 53 whereinsaid double-acting piston includes a piston rod, and said bellowsassembly includes a first flange fixed relative to said double-actingpiston and a second flange secured to said piston rod and therebyreciprocable with said double-acting piston with respect to said firstflange.
 55. The actuator system of claim 54 wherein said ratchet memberis secured to said second flange.
 56. The actuator system of claim 48wherein said double-acting piston is pivotal within and relative to saidprotective sealed chamber assembly.
 57. The actuator system of claim 48wherein said double-acting piston that of and said protective sealedchamber assembly are pivotal about an axis fixed relative to saidratchet wheel.
 58. The actuator system of claim 48 further comprisingsensing means for sensing the position of the rotatable element ascontrolled by said ratchet wheel, said sensing means comprising amagnetic field sensor and at least one magnet mounted on said ratchetwheel.
 59. The actuator system of claim 48 further comprising countingmeans for counting the revolutions of said ratchet wheel.
 60. Theactuator system of claim 48 further comprising a mounting plate disposedsuch that said ratchet member and the rotatable element are positionedon opposite sides thereof.
 61. The actuator system of claim 60 whereinsaid ratchet wheel is rotatable about an axis passing perpendicularlythrough said mounting plate.
 62. An actuator system comprising:apressure vessel containing pressurized hazardous fluid; a rotary elementpositioned in said pressure vessel; a ratchet wheel operativelyconnected to said rotary element such that rotation of said ratchetwheel rotates said rotary element; a double-acting cylinder mountedwithin said pressure vessel, controllable from outside of said pressurevessel and operatively connected to said ratchet wheel to controllablyrotate said ratchet wheel and thereby said rotary element; and a sealedbellows chamber in said pressure vessel and in which said double-actingcylinder is disposed and protectively sealed from the pressurizedhazardous fluid of said pressure vessel.
 63. The actuator system ofclaim 62 wherein said sealed bellows chamber comprises a pair of spacedmounting flanges and a flexible bellows sealed at opposite ends thereofto said flanges.
 64. The actuator system of claim 63 wherein saiddouble-acting cylinder includes a cylinder and a piston reciprocablewith respect to said cylinder, and said mounting flanges include a firstflange fixed relative to said cylinder and a second flange secured tosaid piston and thereby reciprocable by said cylinder and said pistonwith respect to said first flange.
 65. The actuator system of claim 62wherein said sealed bellows chamber is attached at its ends relative tosaid double-acting cylinder so as to flexibly contract and expand withthe reciprocation of said double-acting cylinder.
 66. The actuatorsystem of claim 62 wherein said rotary element comprises a valve. 67.The actuator system of claim 62 wherein said rotary element comprises aquarter-turn rotatable element, and said ratchet wheel has a pluralityof teeth, the total number of which is evenly divisible by four.
 68. Theactuator system of claim 62 further comprising a rotation shaft whichdrives said rotary element through the rotation of said ratchet wheel.69. The actuator system of claim 62 wherein said sealed bellows chambercomprises a flexible bellows having an elongated exterior surfacedirectly contacted by and acted upon by the pressurized hazardous fluid.70. The actuator system of claim 62 further comprising a ratchet memberhaving a distal end engageable with said ratchet wheel to thereby rotatesaid ratchet wheel by the reciprocation of said double-acting cylinder.71. The actuator system of claim 62 further comprising said ratchetmember having a proximal end mounted to said sealed bellows chamber, andbiasing means secured to said sealed bellows chamber for biasing saiddistal end operatively against said ratchet wheel.
 72. The actuatorsystem of claim 62 wherein said sealed bellows chamber includes aflexible reciprocal bellows guided and supported by said double-actingcylinder.
 73. The actuator system of claim 62 wherein said sealedbellows chamber comprises an elongated flexible bellows.